Semiconductors are placed in packages and are then subjected to a variety of electrical and thermal tests. The thermal tests typically entail exposing the package to a series of low and high temperatures, referred to as thermal cycles. For example, it is common to expect a packaged semiconductor to withstand at least 1000 thermal cycles between 1 and 100° C. Additional thermal cycles typically cause damage to the semiconductor. This damage arises largely from the mechanical stress placed on the semiconductor. This mechanical stress stems from the mismatch in the thermal coefficients of expansion between the semiconductor, the substrate upon which it is mounted, and the epoxy bonding it to the substrate.
In view of the foregoing, it would be highly desirable to improve the thermal cycling performance of packaged semiconductors. Preferably, the technique would be low cost and would rely upon known packaging techniques.